Deep Underground Basements for Major Urban Building Construction

Deep underground basements that are integrated into urban development projects early in the overall project design offer many inherent improvements to the overall quality and value of the project and its surrounding community. Diaphragm walls combine into a single foundation unit the functions of temporary shoring, permanent basement walls, hydraulic cutoff, and vertical support elements/shear walls, and, because of this combination, have proven to be an economical alternative in many circumstances. This paper examines the evolution of deep underground basement construction, identifies considerations associated with diaphragm wall construction, and provides several case history examples to illustrate the resolution of key issues.